(a) Field of the Invention
The present invention relates to an organic light emitting device and a manufacturing method thereof.
(b) Description of the Related Art
Trends toward lightweight and thin personal computers and televisions sets also require lightweight and thin display devices, and flat panel displays such as a liquid crystal display (LCD) satisfying such requirements are being substituted for conventional cathode ray tubes (CRTs).
However, because the LCD is a passive display device, an additional back-light as a light source is needed, and the LCD has various problems such as a slow response time and a narrow viewing angle.
Among the flat panel displays, an organic light emitting diode display (OLED display) has recently been the most promising as a display device for solving these problems.
The OLED display includes two electrodes and an organic light emitting layer interposed between the two electrodes. One of the two electrodes injects holes and the other injects electrons into the light emitting layer. The injected electrons and holes are combined to form excitons and the excitons emit light as release energy.
Because the OLED display is a self-emissive display device, an additional light source is not necessary such that the OLED display has lower power consumption as well as a high response speed, wide viewing angle, and high contrast ratio.
The OLED display may be classified as a passive matrix OLED display and an active matrix OLED display according to driving type.
In the active OLED display, an electrode and an emission layer are disposed on a thin film transistor array panel, and the thin film transistor array panel includes driving voltage lines for transmitting a driving voltage as well as signal lines such as gate lines and data lines.
However, the driving voltage lines must be isolated from the gate lines and the data lines, because if the driving voltage lines are disposed close to the gate lines or data lines, a signal delay of the gate lines or data lines may be generated.
To prevent this, each driving voltage line may be formed with a uniform interval from the gate line and data line, but the area that the gate lines, the data lines, and the driving voltage lines occupies is thereby increased such that the aperture ratio may be remarkably reduced.
Also, the driving voltage lines may become disconnected due to steps at an area where the driving voltage lines intersect the gate lines or the data lines.
The above information disclosed in this Background section is only for enhancement of understanding of the background of the invention and therefore it may contain information that does not form the prior art that is already known in this country to a person of ordinary skill in the art.